One of the critical growth and development stages that is vulnerable to drought and heat stress even in hardy staple crops is germination. Sorghum is a critically essential, resilient, and diverse crop that displays genotypic variations in its ability to withstand such harsh conditions, limiting crop stand and ultimately leading to yield losses. Therefore, the goal of this study was to evaluate the performance of 50 high potential genotypes of African sorghum, including landraces, breeding lines and check varieties to simulated drought and heat stress at germination stage. The study used a split plot arrangement for temperature treatments, laid in a completely randomized design with three replications. Final germination percentage, mean germination time, germination index and coefficient variation of germination time (CVt) were determined. Data was subjected to generalized linear model, principal component analysis, hierarchical agglomerative cluster analysis and principal coordinate analysis to determine statistical differences in genotypes and visualize groups of genotypes according to their overall performance in assessed germination parameters. Drought stress and supra-optimal temperatures suppressed and delayed germination. The genotypes were grouped into six distinct clusters based on their performance. Genotypes NPGRC1593, NPGRC1782, NPGRC1476 and IS224426 performed exceptionally well under both stressors and outperformed check varieties in almost all parameters assessed. To improve crop establishment and increase agricultural yields, breeding and crop improvement programs should focus on genotypes that can withstand both stresses.

Eggplant (Solanum melongena L.) is a widely cultivated vegetable in India with enormous variability. Recent molecular techniques revealed three closely related but distinct Solanum species (S. melongena, S. incanum and S. insanum), with the Indian subcontinent being a domesticated centre. Spontaneous hybridization between S. insanum and S. melongena has led to the formation of naturally introgressed lines and limited studies are available to differentiate these genotypes using morphological key traits. Current study aimed to delineate naturally introgressed genotypes of Indian eggplant collections using morphological key traits for plant genetic resources (PGR) management and assess available genetic diversity. The study characterized a collection of 157 eggplant germplasm at ICAR-NBPGR, Regional Station, Kerala, and identified 30 naturally introgressed, 10 wild progenitors and 117 cultivated eggplants. The key morphological traits are prickliness (stem, petiole, calyx and pedicle), leaf base shape, fruit shape and size. Other fruit traits such as length, breadth and mesocarp texture could also provide some clues for delineating introgressed genotypes from S. insanum and S. melongena. Basic statistical analysis of six quantitative traits of 157 eggplant genotypes revealed the presence of considerable amount of variation (CV%) in which fruit length/breadth ratio showed higher variation (73.87) followed by fruit length (54.73) and average fruit weight (53.5). The frequency distribution of 14 qualitative traits revealed the presence of all character states among them. Key traits identified under study could provide clues to identify individual plants at field level to plant taxonomist/explorers and also to aid gene bank curators for PGR management.

The objective of the research was to assess diversity among 50 rice genotypes for ratooning and perennation which refers to ability of a plant to regrow from stubble remaining after harvesting. Results showed that 30 genotypes exhibited different degree of ratoon production and ratoon yield. Diversity analysis revealed that all the ratooning genotypes could be assigned to ten clusters. Clusters III (Binadhan-11 and Sayjihari) and VI (IR-64, DRR-44) were the best performing for ratoon yield. Maximum inter-cluster distance was observed between genotypes falling under clusters III and X followed by genotypes under clusters III and II indicating wider genetic diversity between these genotypes. Thus, these genotypes may be useful for future breeding to develop superior varieties with respect to ratooning ability and ratoon yield.

Despite the increasing demand for diverse Centella asiatica (L.) Urb. species in Korea, studies on related topics are limited, with the majority of studies focusing on functional evaluations, rather than genetic diversity. Therefore, in this study, we explored the genetic diversity of C. asiatica, a valuable medicinal plant collected from six island regions in Korea, using genotyping-by-sequencing analysis. Specifically, we aimed to understand plant genetic variations, population structure and the potential for conservation and genetic improvement. The results indicated relatively high genetic diversity among the samples collected from the six island regions but low genetic differentiation among their populations. Two distinct genetic clusters were identified; however, even within these clusters, genetic differentiation was minimal. The lack of significant isolation-by-distance patterns and evidence of potential clonal spread suggested that some individuals that adapted to colder Korean conditions achieved dominance. This study highlights the importance of assessing the genetic diversity of native C. asiatica in Korea and explores the possibility of conducting follow-up studies to understand the phytochemical content and bioactivity variations among the individuals. This information can aid in the selection of superior resources and effective utilization of plant genetic resources for cultivar development and other applications.

This study investigates the inheritance pattern of petalous and apetalous traits in yellow sarson (Brassica rapa var yellow sarson) and its significance for breeding efforts. Utilizing three crucial crosses between petalous (Pant Sweta, Pant Girija, YSH0401) and ‘apetalous’ parents, we observed the absence of apetalous plants in the F1 generation, indicating dominant inheritance of petalous plants. The F2 generation consistently displayed a 3:1 ratio of petalous to apetalous plants, confirming the dominance of the petalous trait. Chi-squared tests on each generation supported this conclusion. Backcrosses with petalous parents yielded no fruit, reinforcing the dominance of the petalous trait. Chi-squared tests on these backcrosses further confirmed the dominance inheritance pattern. Conversely, backcrosses with apetalous parents consistently exhibited a 1:1 ratio, highlighting the recessive nature of the apetalous trait. The study underscores the importance of understanding the inheritance pattern of petalous and apetalous traits in B. rapa var yellow sarson crop, as it has implications for breeding goals. Knowledge on trait inheritance can guide future breeding strategies, facilitating the transfer of the apetalous trait as needed. This study provides valuable insights for genetic investigations and breeding initiatives in B. rapa var yellow sarson.

Gentiana straminea Maxim. (Gentianaceae) is an important traditional Tibetan herb that is mainly distributed on the Qinghai-Tibetan Plateau. Despite its agricultural and pharmacological importance, there remains a paucity of microsatellite markers, particularly expressed sequence tag-simple sequence repeat (EST-SSR) markers, available for this local endemic species. In this study, based on previous Illumina transcriptome data of G. straminea, a total of 96 EST-SSR markers were initially designed and tested. Thirty-two of 96 loci (33.33%) were successfully amplified and verified for validation. Among them, 10 were polymorphic and had clear bands. The polymorphism information content values were 0.09–0.799, the number of alleles per locus ranged from 3 to 14, and the levels of observed and expected heterozygosity were 0.078–0.722 and 0.238–0.884, respectively, which suggested a high level of information. Moreover, cross-amplification was successful for 10 loci in two other related species, Gentiana macrophylla Pallas and Gentiana dahurica Fischer. These EST-SSR markers provide a valuable tool for investigating the genetic diversity related to quantitative traits and population genetic studies on G. straminea and related species in sect. Cruciata Gaudin.

MicroRNAs (miRNAs) play important roles in regulating salt tolerance in Dongxiang wild rice (DXWR, Oryza rufipogon Griff.). The development of salt-responsive miRNA-simple sequence repeat (SSR) markers will significantly bolster research on DXWR, providing novel tools for exploring salt-tolerant genetic resources and advancing the development of salt-tolerant rice varieties. In the present study, a total of 137 miRNA-SSR markers were successfully developed, specifically derived from miRNAs responsive to salt stress in DXWR. Subsequently, a subset of 20 markers was randomly selected for validation across three distinct DXWR populations, along with 35 modern rice varieties. Notably, 13 of these markers exhibited remarkable polymorphism. The polymorphic markers collectively amplified 52 SSR loci, averaging four alleles per locus. The polymorphism information content values associated with these loci spanned from 0.23 to 0.70, with a mean value of 0.49. Particularly noteworthy is the miR162a-SSR marker, which demonstrated distinct allelic patterns and holds potential as a diagnostic marker for discriminating the salt-tolerant rice varieties from the non-tolerant varieties. This study provides a valuable tool for genetic analysis and precision breeding, facilitating the identification and utilization of valuable salt-tolerant genetic resources.

Gamma ray-induced mutations have been widely used to improve existing crop germplasm and create novel genetic variation. In the current study, a multi-year experiment was carried out to induce and isolate mutants with desirable agro-morphological traits and improved grain hardness through evaluation of induced mutant populations generated in soft-textured wheat variety HPW 89 irradiated with gamma ray dose of 250, 300 and 350 Gy. Mutagen sensitivity studies revealed a higher frequency of biological damage and seedling mortality for doses beyond 300 Gy in the M1 generation. However, the mutagenic treatments in the M2–3 populations significantly altered the magnitude of the biometrical traits. Results from the variability and association studies among traits showed that biological yield per plant, 1000-grain weight, spike length, grains per spike and plant height may be prioritized for higher genetic gain and could be used as selection criteria parameters. Multivariate analysis indicated induction of heterogeneity among mutant populations. Overall, 250–300 Gy doses were found ideal for a successful wheat mutation programme and 293 agro-morphologically superior wheat mutants were identified, out of which 108 had semi-hard grain texture based on single kernel characterization system. Among these, nine mutants were found to have the highest grain hardness index due to induced changes in one or both puroindoline genes. Hence, these mutants identified for several traits along with harder grain texture will serve as important genetic resource in future wheat-breeding programmes.

Pear (Pyrus communis L.) stands out as a prominent fruit species in temperate regions worldwide. The Çoruh River basin, nestled in the lower Caucasus in Türkiye, serves as a valuable repository of pear germplasm. To elucidate the genetic structure of pear populations in this region, 84 village pear cultivar genotypes (land races) from six villages, sample garden collections (SCC), and wild Panta root stock populations were analysed using eleven microsatellite markers. Genetic diversity and structure analyses indicated that village pear cultivar populations exhibit substantial genetic diversity and admixture. This diversity is attributed to local farming practices such as phenotypic selection and widespread dispersal of clonal materials. The genetic structure analysis, combined with the identification of private alleles, indicates that the pear genetic resources in the Çoruh river basin likely has originated from two gene pool sources, specifically the Meydancık and Camili village pear traditional cultivar populations. The Camili village pear cultivar population as a new in situ genetic reserve site has been proposed. Despite the existence an ex situ conservation site, the study suggests inadequateness of SCC as an ex situ site in capturing the full extent of genetic diversity of village pear cultivar genetic resources. Thus, enriching the genetic diversity in the SCC ex situ site is essential for effective pear genetic resource conservation in the Çoruh river basin. These findings contribute valuable insights for the development of targeted conservation strategies, ensuring the preservation of pear genetic resources in this region.

Early morning flowering (EMF) is a desirable trait in rice to avoid heat stress as temperatures in early morning hours are low compared to afternoon and flowering is the most sensitive stage to heat exposure. Cultivated rice accessions including both Oryza glaberrima and O. sativa were phenotyped for an EMF trait in 2016–2018 in two locations viz. Cotonou in Benin Republic and Ibadan in Nigeria. The initial screening was done in Cotonou in three phases in 2016 dry season, 2017 wet season and 2017 dry season, respectively. The 2093 accessions used in initial screening were subdivided into three groups based on flowering duration ensuring that each accession was grown under conditions which were best suited to their flowering duration. Further screening was done in Ibadan in 2018 dry season and 2018 wet season. Out of 2093 accessions taken in the initial screening only 1754 accessions germinated out of which only 64 accessions exhibited EMF phenotype consistently across the cultivated years, seasons and locations. Among the 64 accessions exhibiting EMF phenotype, 15 accessions also showed an early peak in spikelet opening time (EPSOT) trait, more than 80% flowering before 09:00 h. We conclude that 15 O. glaberrima accessions identified possessing both the EMF and EPSOT traits are suitable donors for use in breeding for heat escape in rice.